Newcastle United winger Anthony Gordon left St James' Park on crutches after yesterday's 4-4 draw with Luton.
Gordon, 22, was forced off at half-time during the eight goal thriller.
He was later seen using crutches with his right foot in a protective boot.
Toon manager Eddie Howe later said: It looked like he twisted his ankle.
I wasn't sure on the incident, I didn't see what happened.
"But he was in a lot of pain at half-time and had to come off."